Is endoscopic polypectomy an adequate therapy for malignant colorectal adenomas?: Presentation of 114 patients and review of the literature

PURPOSE: This study was designed to evaluate the outcome of endoscopic polypectomy of malignant polyps with and without subsequent surgery based on histologic criteria. METHODS: Consecutive patients with invasive carcinoma in colorectal polyps endoscopically removed between 1985 and 1996 were retrospectively studied. Patients with complete resection, grading G1 or G2, and absence of vascular invasion were classified as "low risk." The other patients were classified "high risk." Available literature was reviewed by applying similar classification criteria. RESULTS: A total of 114 patients (59 males; median age, 70 (range, 20-92) years) were included. Median poly size was 2.5, p (0.4-10) cm. After polypectomy, of 54 patients with low-risk malignant polyps, 13 died of unrelated causes after a median of 76 months, 5 had no residual tumor at surgery, and 33 were alive and well during a median follow-up of 69 (range, 9-169) months. Of 60 patients with high-risk malignant polyps, 52 had surgery (residual carcinoma 27 percent). Five of eight patients not operated had an uneventful follow-tip of median 57 (range, 47-129) months. Patients in the high-risk group were significantly more likely to have an adverse outcome than those in the low-risk group (P < 0.0001). Review of 20 studies including 1,220 patients with malignant polyps revealed no patient with low-risk criteria with an adverse outcome. CONCLUSIONS: For patients with low-risk malignant polyps, endoscopic polypectomy alone seems to be adequate. In high-risk patients, the risk of adverse outcome should be weighed against the risk of surgery.